Apparatus for cutting tapered elliptical holes



F. E. B. FRIPP'.

APPARATUS FOR CUTTING TAPERED ELLIPTICAL HOLES.

APPLICATION FILED DEC.3I, I918.

1,3&2,%61. V rawntmune 1,19%.

UNITED STATES PATENT OFFICE.

FRANCIS EDWARD BoWLEs FRIPP, or BRoCKENHUnsr, ENGLAND, ASSTGNOB r0 COLINHUN'ILY GORDON, or CHRISTCHURCH, NEW ZEALANI').

Specification of Letters Patent;

Patented June 1, 1920.

Application filed December 31, 1918. Serial No. 269,168.

To all whom it may concern:

Be it known that I, FRANCIS EDWARD BOWLES FRIPP, a subject of the Kingof England, residing at Brockenhurst, Hampshire, England, have inventedcertain new and useful Improvementsin Apparatus for Cutting TaperedElliptical Holes, of which the folv According to this invention, thereis com-' bined with a carrier for the maul-head or other part to beoperated upon, a radius-rod fulcrumed at one end to permit of universalmovement, a templet operatively connected with the radius-rod to limitits movement, and guiding-means to prevent the radius-rod from rockingabout an axis passing through the fulcrum point and the point of contactwith the templet.

Preferably the guiding-means to prevent rocking of the carrier takes theform of a long rod projecting from the carrier or a part secured theretoapproximately radial to an axis passing through the fulcrum point of theradius-rod and the center ofthe figure provided by the templet, and asupport for that'end of the rod remote from the carrier, which supportis such as to permit of endwise movement of the rod and also swingingmovement of the carrier end of the same.

The long rod may be hinged relatively to the carrier to permit ofrelative movement of the carrier and rod but not in the direction inwhich the carrier would tend to rock about the point of Contact with thetemplet. Y

The support for the projecting end ofthe long rod may be so situated ata point halfway between the limits of movement of the carrier in thedirection in which rocking about the point of Contact with the templetis to be prevented so that the slight tilt of the carriercaused by therod occurs'half at the limit of its movement in one direction and halfat the limit of its movement in the other direction. n

In the accompanying drawings which illustrate one method of carrying outthis 1nventi0n:-

Figure l is a side elevation of the apparatus;

Fig. 2 is a plan of the same, and

Fig. 3 is a face view of the templet.

The same letters indicate the same parts throughout the drawings.

The apparatus is built up on cross-slides supported by a table, the topslide 1 only being shown in the drawings Secured to this slide isa'bracket 2 convenientlymade of strip steel bent approximately into theform of a V and turned over at the angle of the ,V so that the fat faceis brought to a horizontal position to support a fulcrumpin 3. Asimilarly shaped radius-rod't extends horizontally from the fulcrum-pin3 and then is bent down at'right-angles and secured to a wooden carrier5. The arms of the radius-rod 4 are secured to opposite sides of thecarrier and they extend upward as at 4 to provide bolts 4 which receivea cross-bar 6 and tightening nuts 7.

The top of the carrier 5 is recessed as at 5 to receive the maul-head 8which is to be operated upon and the maul-head is held firmly in placeby thecross-bar 6 when this is fo igced down upon it by the handled nutsSecured to an inclined block 9 on the slide which extends around oneside of the carrier and there provides an operating-handle 13 and alsoprojects from the other side ofthe carrier as at 13 to provide a bracketto which a long (say 10 ft.) guide-rodl l is connected. The guide-rod isconnectedfto the bracket by a hinge 143 whose axis is verticallysituated,

' could be employed providedthe fit is loose enough to allow of auniversal movement. The object of the second roller or of the plate 16is merely to prevent the end of the rod from being lifted.

The whole device is counterbalanced by a weight not shown in thedrawings but which is connected by a cord 17 to a cross-bar 18connecting the arms of the 'radiusrod'4.

The cutting-tool for operation upon the maul-head is shown at 19.

The operation of this device is as follows V The maul-head 8 to beoperated upon is dropped into the bed provided for it by the carrier 5and the cross-bar 6, which is conveniently in the form of a spring boweddownward at the center, is then dropped over the bolts 4 and pressedhome by the handled nuts7. The'cross-bar thus grips the maul firmly inplace. The whole device is then moved bythe cross slides up to the tool19 whichris shaped to cut at its end as well as at its sides.- Themaul-head is pressed against the end of the cutter and by the handle 13it is made to move in the elliptical path provided by the templet 10.Asthe maul is thus fed forward and around in an elliptical path, thecutter enters the maul and cuts a tapered elliptical hole, the degree oftaper depending upon the length ofthe radius-rod 4.

Booking of the arm about the point of contact of the templet-pin 11 withthe templet is prevented by the long guide-rod 14. The carrier can moverelatively to the rod 14-. by means of the hinge 14 as it swings in ahorizontal plane but the axis of thehinge being placed verticallyprevents rocking of the carrier 5relatively to the rod 141. The carrier,however, swingswith the rod in a vertical plane as it risesand falls bythe engagement of the pin 11 with the templet 1O and-thechanges of pathin this direction due to the action of the guide-rod is equalized at thetop and bottom of the elliptical channel 10 by so situating the roller15 that the center of the rod at the far end lies in the same horizontalplane as the axis X whichpasses through the fulcrum of the radius-rodand the center of the elliptical figure provided by'the'templet.

The cutter ispreferably formed offhighspeed steel having theusualthree'ior more vided with adjusting means.

. What I claim as my invention and desire to secure by Letters atentis 1. In apparatus for cutting tapered elliptical holes, the combinationwith a carrier for the maul-head or other part in which the hole is tobe cut, of a radius-rodsfulcrumed at one end in such manner as to permitof unlversal movement, a templet operatlvely connected with theradius-rod to limit its movement, and guiding-means toprevent theradius-rod from rocking about an axis passing through the fulcrum-pointand the point of contact with the templet.

2. Apparatus for cutting tapered elliptical holes according toclaiming-clause No. 1 wherein the guiding-means to prevent rocking ofthe carrier takes the formof a long rod projecting from the carrier or apart secured thereto approximately radial to an axis passing through thefulcrum point of the radius-rod and the center of the figure provided bythe templet, and a support for that end of the rod remote from thecarrier which support is such as to permit of'endwise .movement of therod and also swinging movement of the. carrier end of the samesubstantially as described.

3. Apparatus for cutting taperedelliptical holes according toclaiming-clause No. 2 wherein the long rod' constituting the guide toprevent rocking is hinged at the carrier end to permit of relativemovement between the rod and carrier but not in the direction in whichthe carrier tends to rock about the point of contact with the templet.

1. Apparatus for cutting tapered elliptical holes according toclaiming-clause No. 1 wherein the templet is situated away from theoperating position of, the tool (for example near the bottom of thecarrier) and has that face whose periphery provides the working edge atright-angles to an axis passing through the fulcrum point of theradius-rod and through the'center of the finger provided by the templetsubstantially as described.

5. Apparatus for vcutting tapered ellipway between the limits ofmovement of the carrier in the direction 'in which rocking I about thepoint of contact with the templet is to be prevented so that thejslight'tilt'of the carrier caused by the rod occurs half at the limit of itsmovement in one direction and half at the limit of its movement in theother direction.

6. Apparatus for cutting tapered elliptical holes according toclaiming-clause No. 1 wherein the carrier With a supporting bracket forthe fulcrum end of the radiusrod is secured to a sliding table to Whichthe templet may also be secured, substantially 10 as described.

In testimony whereof I afiix my signature.

FRANCIS EDWARD BOWLES FRIPP.

